This project is directed at analysis of the hormonal and ionic basis of excitation in uterine smooth muscle. In terms of my long-range goals, these studies are designed to provide insight into the hormonal mechanisms controlling uterine function during pregnancy and parturition. The specific experimental approaches used include: (1) voltage-clamp studies on action potentials and slow waves; (2) tissue culture of the myometrium and microelectrode recording from cells in culture; (3) hormonal effects on action potentials, slow waves, and smooth muscle cells in culture; (4) computer modeling of smooth muscle using modified Hodgkin-Huxley equations.